I ran new #2 high grade electrolytic grade copper from back of engine to firewall where the factory ground was and used a good star washer, ran another ground using the same copper wire from chassis to block, with new battery cables from block to battery. 6AL is grounded direct to battery, constant is hooked directly to battery, ignition is ran with a new wire to the fuse box and all have 14.5 volts running under load. Fired car this morning and it has the same issues. At this point, having tested everything, I am almost 100% positive that the Pro Billet, which is the older 8555 unit, is the issue. It's te last piece of the puzzle in my opinion... I plan to contact ATK engines, they built the engine for Year One, tomorrow to find out what they think. Unless I can find another Pro Billet close by to try. Right now timing is at 16 degrees initial and 36 total with the black stop bushing, and I have the light silver springs in it. I had the blue springs in before and there was no change. Also took the Autolite plugs to .045 instead of the factory gap of .038